FIG. 1 is a cross-sectional view of a conventional heating process apparatus 10. A heating process chamber 11 is a chamber made of water-cooled aluminum with a reflectance improved by mirror finishing of its inner wall and has a fluid flowing section 19 in which a cooling fluid can flow. The heating process chamber 11 can be evacuated to a vacuum of approximately 10−2 Pa. However, a heating process can also be performed at atmospheric pressure.
A heater 13 including a filament and a filament power supply is contained inside a heat-processed object support member (susceptor) 12 coated with a coating layer A of pyrolytic carbon. A substrate 14 to be subjected to heating process is placed on the heat-processed object support member 12 on the upper side in FIG. 1. A thermo coupler 15, 16 is disposed on the heat-processed object support member 12 with the substrate 14 placed on its upper side, thereby allowing heating temperature to be sensed. The substrate 14 is heated by applying a predetermined voltage to the filament by the filament power supply to accelerate thermoelectrons generated from the filament to bombard them onto the heat-processed object support member 12 to generate heat. The heater 13 may be a thermoelectron generator for electron bombardment heating or an infrared lamp for infrared lamp heating.
The interior of the heat-processed object support member 12 can be evacuated by a vacuum pump system different from that for the heating process chamber 11 constantly to a vacuum of approximately 10−2 Pa or less. For controlling the temperature in the heating process apparatus 10, the thermo coupler 16 of tungsten-rhenium (W—Re) is inserted through a port 18 in a side of the heating process chamber 11 into a groove in a side of the heat-processed object support member 12 to measure and control the heat-processed object support member 12 (Patent document 1).
Patent document 1: Japanese Patent Application Laid-Open No. 2000-36370
However, the conventional heating process apparatus 10, which uses the thermo coupler 16 to control the temperature of the heat-processed object support member 12, has problems that the thermo coupler 16 does not make direct contact measurement since the thermo coupler 16 is simply inserted in the groove in the side surface of the heat-processed object support member 12 and that the temperature of the cap 17 and the temperature of the substrate 14 cannot be correlated to each other since the temperature of a location on the side surface of the heat-processed object support member 12 has a steep temperature gradient. In addition, the tungsten-rhenium (W-Re) thermo coupler 16 used in the conventional heating process apparatus 10 deteriorates and breaks so that it becomes unable to accomplish temperature control at high temperatures higher than or equal to 1850 degrees, and therefore cannot cover the temperature range (1550 to 2400 degrees) required in the heating process by the apparatus. Therefore, an object of the present invention is to solve these problems and provide a heating process apparatus consistently capable of controlling to a constant temperature and controlling in a high-temperature range higher than or equal to 1850 degrees.